88 INSECTS WHICH PEEY UPON AGEICULTURAL PLANTS. 



HE^IDIETABOLA. 



H E M I P T E E A. 



The mouth is a beak-shaped sucking organ, suited for imbib- 

 ing the juices of plants. The male has generally two pairs of 

 wings, while the female is wingless. The larva differs from the 

 imago chiefly in having no wings and in being smaller in size. 



Sub-order, Homopteea. 



AjjJiis fahce (the Bean Aphis). — This insect is known in the 

 country as the " collier fly " or " black dolphin." The females 

 suddenly appear in large quantities on the leaf-stalks of the 

 beans, and being viviparous multiply with extreme rapidity. 

 They suck the sap and exhaust the plant, so that the crop is 

 greatly injured or destroyed. The females are of a sooty black 

 colour, have a pear-shaped body, and are about the eighth of an 

 inch in length. The males are also black, but are much smaller, 

 and have four membranous wings. The only way to deal with 

 them is to cut off the infected tops, and crush them with the 

 foot. As it is the wingless females which do the damage, they 

 cannot easily regain the stalks ; but perhaps the best way is to 

 carry off the cut tops and destroy them. ' This operation need not 

 be expensive or tedious, as many farmers do it to cause the 

 plants to " pod " better, when otherwise healthy enough. 



Aiohis 2^'isi (the Pea Aphis) is large and of a light green colour, 

 being called the "green dolphin" in the country. There are 

 both winged and wingless females — both viviparous. The male 

 is winged, and black or brown, with long antenuce or "feelers." 

 It infests many plants besides the pea, notably vetches, lentils, 

 sainfoin, clover, &c. There are no means of saving the crop 

 when it becomes attacked, as the wing;ed females can remove 

 from place to place, so that it must be cut and used imme- 

 diately, giving it to cattle and pigs, or if the crop is too far gone, 

 rolled down and ploughed in, and a catchcrop tried. 



A]jliis ccrealis, A. avence, or A. granaria (as it is known by 

 these three names). — This (the Corn Aphis) infests all the corn 

 crops, and is plentiful in the month of July. The females 

 crowd on the young ears, and by sucking the juices hinder the 

 full development of the grain. They go through the same 

 phases as other aphides, and are of a red, green, brown, or yellow 

 colour, with a distinct lobe and a row of black dots on each side. 

 The females are often apterous. The Aijliiclms avence, an 

 ichneumon parasitic fly, with long filiform antenUcT, keeps them 

 in check. The females of this species bend their abdomens 

 under their victim, insert their ovipositor into the belly of the 



